This protocol is a means to introduce medical students to clinical research through the design and execution of a clinical study and the analysis and presentation of the research data. The study looks at the control of insulin secretion by various stimuli and cardiovascular responses to adrenergic agents: (1) effect of epinephrine on glucose-stimulated insulin secretion, (2) effect of arginine and isoproterenol on insulin secretion, and (3) effect of exercise on glucose and insulin secretion and on plasma catecholamines.